Results 21 to 30 of about 5,650 (230)
Searching for overlooked TDEs in the 4XMM catalogue
Astronomische Nachrichten, Volume 344, Issue 4, May 2023., 2023 Abstract Tidal disruption events (TDEs) are usually discovered as bright transients, either in the X‐ray or optical/UV band. These events are often characterized by a “super‐soft” emission in the X‐ray band, which has not been observed in any other extragalactic source, with few exceptions (novae and supersoft active galactic nuclei, AGN), which can ...
Andrea Sacchi +2 more
wiley +1 more source
Supermassive Black Holes [PDF]
Journal of High Energy Physics, Gravitation and Cosmology, 2019 In the following black hole model, electrons and positrons form a neutral gas which is confined by gravitation. The smaller masses are supported against gravity by electron degeneracy pressure. Larger masses are supported by ideal gas and radiation pressure. In each case, the gas is a polytrope which satisfies the Lane-Emden equation.
openaire +2 more sources
Winds in ultraluminous X‐ray sources: New challenges
Astronomische Nachrichten, Volume 344, Issue 4, May 2023., 2023 Abstract Ultraluminous X‐ray sources (ULXs) are extreme X‐ray binaries shining above 1039 erg/s, in most cases as a consequence of super‐Eddington accretion onto neutron stars and stellar‐mass black holes accreting above their Eddington limit. This was understood after the discovery of coherent pulsations, cyclotron lines, and powerful winds.
C. Pinto, P. Kosec
wiley +1 more source
Shadow of rotating and twisting charged black holes with cloud of strings and quintessence
European Physical Journal C: Particles and Fields, 2023 Testing gravity theories is an important and interesting issue in relativistic astrophysics using astrophysical observations. In recent years, Event horizon telescope collaboration provided valuable data from shadow of supermassive black holes located at
Muhammad Zahid +4 more
doaj +1 more source
Shadow of a rotating squashed Kaluza-Klein black hole
Journal of High Energy Physics, 2019 We study the shadow of a rotating squashed Kaluza-Klein (KK) black hole and the shadow is found to possess distinct properties from those of usual rotating black holes.
Fen Long +3 more
doaj +1 more source
A Global Inventory of Feedback
Galaxies, 2023 Feedback from both supermassive black holes and massive stars plays a fundamental role in the evolution of galaxies and the inter-galactic medium. In this paper, we use available data to estimate the total amount of kinetic energy and momentum created ...
Timothy M. Heckman, Philip N. Best
doaj +1 more source
Supermassive Black Holes in Bulges [PDF]
The Astrophysical Journal, 2001 26 pages, 11 Postscript figures, accepted for publication on ...
Sarzi, Marc +7 more
openaire +2 more sources
Fourier spectral‐timing techniques for the study of accreting black holes
Astronomische Nachrichten, Volume 344, Issue 4, May 2023., 2023 Abstract The X‐ray signal from active galactic nuclei and black hole (BH) X‐ray binaries is highly variable on a range of timescales. This variability can be exploited to map the region of interest close to the BH, which is far too small to directly image for all but two BHs in the Universe.
Adam Ingram
wiley +1 more source
Supermassive black hole ancestors [PDF]
Monthly Notices of the Royal Astronomical Society, 2012 12 pages, 9 figures, 1 table, MNRAS in ...
Petri, Andrea +2 more
openaire +3 more sources
Mass Functions of Supermassive Black Holes across Cosmic Time
Advances in Astronomy, 2012 The black hole mass function of supermassive black holes describes the evolution of the distribution of black hole mass. It is one of the primary empirical tools available for mapping the growth of supermassive black holes and for constraining ...
Brandon C. Kelly, Andrea Merloni
doaj +1 more source